Heat exchanger



FIG. 1 is a perspective view of a heat exchanger embodying the invention.

FIG. 2 is a left side view of the heat exchanger shown in FIG. 1.

FIG. 3 is a right side view of the heat exchanger shown in FIG. 1.

FIG. 4 is a top view of the heat exchanger shown in FIG. 1.

FIG. 5 is a bottom view of the heat exchanger shown in FIG. 1.

FIG. 6 is a rear view of the heat exchanger shown in FIG. 1; and,

FIG. 7 is a front view of the heat exchanger shown in FIG. 1.

The elements shown in broken lines are included for the purpose of illustrating environment and form no part of the claimed design. The portions shown in broken lines having unequal length segments illustrate the boundary of the claimed design and form no part of the claimed design. 

CLAIM The ornamental design for a heat exchanger, as shown and described. 